Machine tool



Saint. 24, 1940- J. B. ARMITAGE MACHINE 'IDOL Original Filed June 22, 1936 8 Sheets-Sheet l ATTORN EY R O T N E V m ELY/57225. ARMZTAEE Sept. 24. 1940. J. B. ARMITAGE 2,215,634

MACHINE TOOL Original Filed June 22, 1936 8 Sheets-Sheet 2 INVENTOR /Z75EPHZ7 4R1=1 7T45E WA W W ATTORNEY l 1940. .1. B. ARMITAE 2,215,534

MACHINE TOOL Original Filed June 22, 19556 8 Sheets-Sheet 3 FZEiJ INVENTOR L/ZYEPHEAEMTA 55 ATTORNEY Sept. 24, 1940. J. B. ARMITAGE MACHINE TOOL Original Fild June 22, 1936 8 Sheets-Sheet 4 NNN Sept. 24, 1940.

J. B. ARMITAGE MACHINE TOOL Original Filed June 22, 1936 8 Sheets-Sheet .5

INVENTOR B47EFHEAJM7ZEE m 19 W ATTORNEY Sept. 24, 1940.

J. B. ARMITAGE MACHINE TOOL Original Filed June 22, 1936 8 Sheets-Sheet 6 I my um" I INVENTOR BfilE EiZfljEMTHEE W AT'i'ORNEY t-" 24, 1940- J. B. ARMITAGE 2,215,684

MACHINE TOOL 8 Sheets-Sheet '7 v Original Filed June 22, 1936 HINVENTOR L/L-75EFHE ARMTAEE,

Sept. 24, 1940. ARMlTAGE 2,215,684

MACHINE TOOL Original Filed June 22, 1936 8 Sheets-Sheet 8 INVENTOR JasEPH f7. ARM 7A 55 ATTORNEY aiente d sept. 24, 1940 UNITED STATES- PATENT OFFICE MACHINE TOOL Joseph B. Armitage, Wauwatosa, Wia; assignor to Kearney & Trecker Corporation, West Allis,

Wis., a corporation of Wisconsin Application June 22, 1936, Serial No. 86,559

Renewed December 17, 1938 A 70 Claims.

supporting and the tool supporting elements.

thereof.

A general object of the invention is to provide a milling machine of improved design that is adapted for convenient and rapid operation and that is of simple and rugged construction.

Another object of the invention is to provide a milling machine that is especially adapted for rapid automatic operation. m Another object is to provide a milling machine of the knee and column type in which all of the feed rate changing gearing and the controls for power operation of the work feeding mechanism are carried by an improved saddle structure.

Another object is to provide a milling machine having an improved saddle structure adapted to support the work-holding table at minimum distance above the knee.

Another object is to provide a milling ma- 2c chine having a knee and saddle structure of novel construction with compartments in the saddle for rate changing and control mechalilSm.

Another object is to provide a milling machine 3d having a hollow saddle disposed to encircle the lmee in manner to provide an oil reservoir in the saddle beneath the knee". to

Another object is to provide a milling machine saddle arranged to contain a relatively large 35 quantity of liquid and provided with cooling fins for cooling the liquid .therein.

Another object is to provide a milling machine in which the operation of the tool spindle Jill is controlled by mechanism mounted on the.

40 saddle.

Another object is to provide control means carried on the saddle of a milling machine for stopping the machine spindle automatically when the table is to be operated at rapid traverse rate.

45 Another object of the invention is to provide a hydraulic control system for a milling machine arranged to control the operation of apparatus in the machine column from control means on a movable work supporting element, in which only 50 a single hydraulic connection is required from the movable member to the column.

Another object is to provide an improved transmission and improved control means'therefor, particularly where different transmission-portions to be controlled are carried by relatively movable structure portions and especially where certain of the control mechanisms for the difl'erent transmission portions are dependently operative or interlocked for dependent or simultaneous transmission effects.

Another object is to provide an improved power shifting means for the shiftable elements of a machine tool transmission, and preferably of hydraulically operable form, and in a form for improved dependent or simultaneous operation of different shiftersf-and especially where different of the shifters are carried by relatively movable supports.

Another object of the invention is to provide a hydraulic control system in which a primary Source of pressure is arranged to actuate a mechanism and a secondary source of pressure is arranged to exert pressure through a single passageway upon a pilot valve to control'the actuation of the mechanism by the primary source. 29

Another object is to provide improved power shifting means for different machine tool transmission elements in which different of the shifters are provided with different power sources, particularly where the shifters are hydraulically operable; but the control means for the different shifters'are power operable dependently or simultaneously from a common power source, at least as to certain control functions; and particularly where the controlmeans is hydraulically 3o operable, and especially where the different control devices or shifter devices are carried by diiferent relatively movable supports.

Another object is to provide a power' operable shifter for a machine tool transmission con- "trolled to be alternately shifted to different positions from a single pressurefluid channel in accordance with pressure variations in the channel, particularly where the structure and arrangement is such that the channel connectsbetween different relatively movable supports car rying different portions of the mechanism, and

' especially where the shifter is to be operated. de-

pendently or simultaneously with another shifter or controller carried by a relatively movable support. 7

Another object is to provide a shifter device primarily operated from one fluid pressure source and a control device for the shifter which is operated from another pressure fluid source,

particularly where the shifter and controller are relatively movable. and especially where the controller is associated with other controllers to be dependently or simultaneously operated.

Another object is to provide improved powershifting means for machine tool transmission elements in which certain of the control members for effecting power connection with the different shifters are hydraulically operable and position of a pilot valve associated therewith, the

pilot valve being actuated by a second pump carried by a movable work supporting element of the machine and acting through a single hydraulic lead extending from the work support to the frame.

A further object is to provide, in a hydraulic control system for a machine tool, a control valve that may be turned by means of a manual control lever through a predetermined operating angle to effect a control operation, and that may be adjusted angularly relative to its manual control lever to aposition efiecting a different control action when the lever is turned through the predetermined operating angle. v V

A further object is to provide an improved hydraulically operated rapid traverse clutch for a machine tool.

A further object is to provide means for preventing coasting of a movable element of a machine tool when the rate of movement thereof is changed from rapid traverse rate to feed rate.

Another object is to provide work support transmission and control mechanism similar to that shown in the cc-pending applications Serial No. 36,766, filed August 19, 1935, Patent No. 2,077,434, April 20, 1937, and Serial No. 65,774, filed February 26, 1936, Patent No. 2,118,357, May 24, 1938, but in an improved and simplified form and especially in a form particularly adapted to use in knee type milling machines.

According to this invention as it is embodied in a milling machine of the knee and column type, the control mechanism for effecting movement of the work supporting table is carried by a saddle of novel construction slidably mounted on the knee, and power for actuating the table at feed rate and at rapid traverse rate respectively is transmitted to the mechanism in the saddle by means of two independent constant speed shafts, the feed rate shaft being driven by the spindle operating clutch and the rapid traverse shaft being driven independently of the spindle clutch. In order to form a rigid and strong construction accommodating all of the control mechanism, and to provide for a generous supply of lubricating and actuating liquid, the saddle structure is made hollow in generally annular configuration and is disposed to encircle the knee in such manner that the knee protrudes through a central opening therein. Manually operable means for eflecting vertical movement of the knee and horizontal movement of the saddle are mounted in the knee in manner to be operable from the front thereof. The hollow saddle houses feed rate changing mechanism and rapid traverse mechanism in a compartment disposed at one side of the knee, and at the other side of the knee it houses hydraulic control mechanism, the lower portion of the saddle beneath the knee serving as a reservoir of large capacity for the actuating liquid. are formed circumferentially on the lower part of the saddle to act as stiffening ribs and to present cooling surfaces for cooling the liquid in the reservoir. The hydraulic control mechanism in the saddle is operated by a pressure pump therein and is arranged to effect automatic reversing of the direction of table movement by trip dogs on the table, movement of the table being at all times under the control of a manual control lever mechanically connected in manner to operate independently of the trip dogs. To control the operation of the tool spindie, there is provided in the column a hydraulically operated main clutch having 'a spring urged pilot valve arranged to be actuated by pressure exerted through a single flexible conduit from the pump in the saddle, bothmanually controlled and automatically actuated means being provided on the saddle for controlling the actuation of the pilot valve to thereby control the operation of the main clutch by means of pressure from a pump in the column. A special control valve is provided that may be adjusted to effect both manual and automatic control of the spindle clutch or to effect manual control only thereof. Automatic reversing of the table at rapid traverse rate is effected by the hydraulic control system acting upon ahydraulically actuated rapid traverse clutch of improved design.

The foregoing and other objects of the invention'which will become more fully apparent from the following detailed specification, may be achieved by the particular machine tool described herein by way of example, as illustrating a preferred embodiment of the invention, in connection with the accompanying drawings, in which:

Figure l is a view in left side elevation of a milling machine of the knee and column type embodying the features of this invention.

Fig. 2 is a vertical sectional view through the column taken on the line 2-2 of Fig. 1 showing the main drive pulley and speed change mecha nism.

Fig. 3 is a vertical sectional view through the column taken on the line 33 of Fig. 2 showing the spindle drive mechanism and speed change gears.

Fig. 4 is a view in front elevation of the milling machine work supporting structure with parts broken away to show the driving and control mechanism.

Fig. 5 is a developed view of the work supporting mechanism taken substantially along the line 55 of Fig. 4 and showing the driving mechanism for actuatingthe work supporting table.

Fig. 6 is a vertical longitudinal sectional view of the work supporting table taken substantially along the line 6-6 of Fig. 7.

Fig. 7 is a horizontal sectional view of the saddle taken on the line 1--1 of Fig. 5.

Fig. 8 is a horizontal sectional view of the milling machine knee taken on the line 8-8 of Fig. 4.

Fig. 9 is a view in vertical section of the knee taken substantially along the line 9-9 of Fig. 8.

Fig. 10 is a vertical sectional view of the table controlling trip mechanism taken substantially along the line l0-l0 of Fig. 4.

Fig. 11 is a vertical sectional view of part of the saddle taken substantially along the line ll--|I of Fig. 6, showing the spindle clutch controlling valve.

Fig. 12 is a diagrammatic view showing the dethe milling machine therein illustrated as a preferred embodiment of this invention is of the well-lmown knee and column type. As shown in Fig. 1, the machine comprises generally an upstanding column or frame 2| that has rotatably mounted in its upper part a horizontal tool supporting spindle 22, and that has slidably mounted above the spindle the usual overarms 23 disposed in cooperating relation thereto. Beneath the tool spindle 22 there is provided superimposed relatively movable work supporting members including a knee 24 that projects from the column 2| and is slidably mounted on the forward face 25 thereof for vertical movement therealong. Slidably mounted upon the knee 24 for horizontal cross movement toward and from the column face 25, is a saddle structure 26 of novel construction that supports on the top thereof a horizontal work supporting table 21 for longitudinal reciprocatory movement tranversely to the direction of movement of the saddle 26, whereby a work piece thereon may be moved in cooperative cutting relationship with a tool mounted in the spindle 22.

Power for rotating the spindle 22 and for reciprocating the work table 21 is derived from a motor in the base of the column 2| that drives a pulley3| by means of multiple belts 32, Fig. 2, the pulley being supported at the right side of the machine by means of an inwardly extending hollow sleeve or hub portion 33 that is iournaled in a clutch pulley bracket 34 mounted in an opening in the right side of the column 2|. Within the hollow hub 33 of the power driven pulley 3| there is rotatably mounted a hollow main drlving shaft 35 which may be operatively connected selectively at its outer end to the pulley 3| by means of a friction clutch-36, the shaft being connected at its inner end within the column 2| to a bevel pinion 31 constituting part of a spindle driving transmission train housed within the column 2|.

For operating the friction clutch 36, there is providedhwithin the hollow driving shaft 35 a clutch operating "rod 36. the outer end of which is arranged to actuate clutch engaging fingers 39 by means of a cone 49, upon axial movement of the rod 38, the clutch and its actuating mechanisni together with the pulley 3| and belts 32 being enclosed and protected by a louvered door or cover 4| hinged on the right side of the column. The clutch actuating rod 36 is connected at its inner end within the column, with a grooved clutch operating'collar 42 arranged to impart longitudinal movement to the rod. Upon moving v the clutch actuating rod 38 to the right, as shown in Fig. .2, by means of the collar 42, the clutch 36 is engaged to drive the main shaft 35. When the rod 38 is moved to the left by the collar, the

clutch is disengaged to permit the pulley 3| to turn freely on the shaft 35, and upon further movement of the collar 42 to the left a friction brake mechanism 43 is engaged to quickly stop rotation of the shaft 35 train in order to quickly stop the tool spindle 22.

The beveled driving pinion 31 at the inner end of the main shaft 35 meshes with'two similar beveled pinions 46 and 41 shown in Fig. 3 and that are rotatably mounted on a shaft 48 journaled at right angles to the main shaft 35 in a removablespeed changing gear box 49 that is supported within an opening in the left side of the column 2| by means of a cover plate 50 constituting part of the box-and fastened to the outside of the column, as shown in Fig, 2. Splined and the spindle driving I on the shaft 43 between the beveled gears 46 and 41 is a clutch collar 5| that may be moved to engage either of the gears by means of a shifter yoke 52 that is pivotally mounted in the gear box and. that may be operated by a plunger 53 extending through the cover plate 53. The plunger 53 is provided on its projecting end with an operating knob 54 whereby it may be moved in or out to shift the clutch collar 5| into en gagement with either the gear 46 or the gear 47 thereby constituting a reversing mechanism for controlling the direction of rotation of the shaft 43 and thereby determining the direction of romechanism that is meshed one at a time with gears 62 and 63 respectively fixed on a shaft 64 that is also journaled in the gear box 49, the arrangement constituting a primary rate changing element of the speed changing mechanism 60.

Above the shaft 64 and parallel thereto is arranged another splined shaft 65, that is journaled at its ends in the front and back respectively of the column 2| and that has slidably mounted thereon three gear couplets 66, 61, and 66. The couplets 66 and 61 constitute parts of a secondary element of the speed changing mechanism, the gears of the couplet 66 being .disposed to be meshed selectively one at a time with the gear 63 and a gear 69 respectively fixed on the shaft 64, and the gears of the couplet 6'! being disposed to be meshed one at a time with gears II and 12 respectively fixed on the shaft 64.

The gear couplet 68 on the splined shaft constitutes part of a tertiary rate changing element and comprises a pinion 13 and a relatively large gear wheel 10, the pinion 13 being adapted to mesh with a relatively large gear wheel 14 fixed on the tool spindle 22 and the gear wheel I0 being adapted to mesh with a small gear wheel 63 on the spindle 22, the arrangement being such that only one pair may be in mesh at a time.

The mechanism for shifting the various gear couplets to effect the desired speed of the spindle 22 is similar to that disclosed and claimed in co-pending application S. N. 86,382, filed June 20, 1936, Patent No.- 2,182,421, December 5, 1939, and is shown generally in Fig. 2. As there shown, the gear shifting mechanism includes a primary shifting lever 15 carried on a shaft 16 rotatably mounted inthe cover plate 59 and having at its inner end a shifting crank member 11 that engages the gear couplet 6| in manner to shift it into operating engagement with either the gear 62 or the gear 63 on the shaft 64, whereby the shaft 64'may be driven at either-oftwo-speeds selectively. Mounted concentrically with the pri mary shifting lever-|6 is a secondary shifting,

lever 18 that is fixed on a sleeve which encircles the shaft 16 and extends through the cover plate 56 and that has on its inner end a plate cam 80. The plate cam 80 is arranged, as more fully described in the previously mentioned cotive gear connections between the shaft 66 and the shaft 64, the shaft 65 may be driven at any one of eight speeds by suitably positioning the primary shifting crank and the secondary shifting crank 18.

The gear couplet 68 constituting part of the tertiary speed changing device may be shifted by means of a tertiary shifting lever 85, shown in mid-position in Fig. 2, that is rotatably mounted by means of a shaft 86 extending through the cover plate 50 and that has at its inner end a shifting crank 81 engaging a slidably mounted shifting yoke 66 that engages the gear couplet 66. The tertiary crank 85 is provided with a locking pin as that may be engaged with either of 'plate 50 two positioning holes 90 and SI Fig. 1 in the cover corresponding with opposite horizontal positions assumed by the lever in positioning the gear couplet 68 to engage the .pinion 16 with the gear 14 or the gear 10 with the gear 63, respectively.

Inasmuch as theshaft may be rotated at eight different speeds by suitably adjusting the primary and the secondary rate changing devices,

the spindle 22 may be operated at eight different speeds in a slow major range when the pinion 13 is in mesh with the gear wheel 14 as shown in Fig. 3, and at eight different speeds in a fast major range when the gear wheel 10 of the couplet 66 is in mesh with the gear wheel 83 on the spindle 22, making a total of sixteen different speeds at which the spindle maybe operated. As more fully described in the previously mentioned co-pending application, an indicating dial 92 Fig. 1 is arranged to cooperate with the three gear shifting levers to indicate the rate of speed at which the spindle is being operated as the result of positioning the three levers.

As shown in Figs. 8 and 9, the knee structure 24 for supporting the saddle and table is relatively narrow and is of hollow construction forming a housing enclosing elevating mechanism including an elevating screw 06 connected by bevel gearing 66 to an elevating shaft 91 which extends from the front of the knee and is provided with a squared end 96 for receiving an operating crank. Adjacent to the elevating shaft 91 there is provided a cross traversing shaft I00 that presents a squared and IM for receiving an operating crank and that is threaded at its inner end to engage a nut I02 fixed on the saddle 26 in such manner that the saddle may be moved toward or from the column by turning the shaft I00 in appropriate direction.

Referring to Fig. 5, the table 21 is ordinarily moved longitudinally relative to the saddle 26 by power means, including two vertically disposed drive shafts I04 and I05 respectively mounted in the column 2| and operatively connected to be driven from the driven pulley 3|, as more fully explained in the aforesaid co-pending application. As shown in Fig. 2, a gear I06 rotatably mounted on the pulley bracket 34 is driven by a gear I06 fixed to the sleeve 33 of the driven pulley II in manner to be driven directly by the pulley whenever the pulley is operating, the gear I06 being operatively connected to drive the vertical shaft I04, as shown in detail in the previously mentioned co-pending application, in manner to transmit power at. constant speed. for rapid traverse movement of the table 21. A gear I01 mounted on the main driving shaft 36, which is connected to be driven by the pulley 3| through the clutch 36, operates to drive the vertical shaft I I06 whenever the clutch 36 is engaged to drive the spindle 22,'and it transmits power to the shaft I05, by mechanism shown in the previously mentioned co-pending application, in a manner to provide power for driving the table 21 at feed rate.

, A shownin Fig. 5, the vertical shafts I04 and I05 pass downward through a rearwardly extending bracket I I0 carried by the vertically movable knee 24, the shaft I04 being operatively connected by gearing III to a horizontally disposed shaft II2 journaled in the bracket IIO, the shaft II2 constituting a constant speed driving means for driving the table 21 at rapid traverse rate. The vertical shaft I05 is operatively connected by gearing II3 to drive a horizontal shaft II4 journaled in the bracket IIO, the shaft II4 constituting a constant speed driving means for driving the table 21 at a selected feed rate.

Inasmuch as it is not necessary to provide power driving connections for moving the knee vertically or for moving. the saddle horizontally \relative to the knee, all of the mechanism for power movement of the table 21 is arranged to be carried directly by the saddle 26 in manner to be directly connected to the table 21 and to be movable bodily with the saddle toward or, from the column, the constant speed rapid traverse driving shaft H2 and the constant speed feed rate driving shaft II4 being arranged to have sliding connection with transmission mechanism in the saddle.

In order to accomodate transmission and control mechanism and to provide ample capacity for lubricating and actuating liquid, the saddle 26 is made hollow and is so shaped as to entirely encircle the knee' 24. As best shown in Fig. 4 the saddle 26 is of generally annular configuration and comprises essentially a relatively thin top cross piece or saddle plate II1 that is slidably mounted on the top of the knee 24 and that is connected at each end with the ends of a U- shaped hollow reinforcing member or yoke II6 conforming to but spaced from the sides and bottom of the knee 24, the arrangement being such that the table 21 is supported at minimum height above the knee thereby improving the rigidity of the structure. The U-shaped hollow member II8 provides at the right side of the knee 24 a compartment IIO for driving mechanism and at the left side of the knee 24 a compartment I20 for control mechanism, the lower portion connecting the compartment H9 and I20 constituting a reservoir I2I of large capacity for lubricating oil that also serves as operating liquid for the hydraulic control mechanism. In order that the liquid in the reservoir I2I may be cooled, the U- shaped member H6 is provided on its sides and bottom with circumferentially disposed cooling fins I22 that function also as reinforcing ribs for stiflening the saddle structure.

As shown inFig. 5, power for moving the table at feed rate is transmitted from the horizontal constant speed feed shaft II4 to a co-axially disposed shaft I24 journaled in the transmission compartment II! of the saddle and having telescopic splined connection with the shaft II4 to permit relative longitudinal movement there-between. At its forward end the shaft I24 is provided with a spur pinion I25 meshing with a gear I26 on a horizontal shaft I 21 constituting part of a rate changing mechanism I26 for adjusting pick-off gears of different the rate of feed at which the table may be driven by the constant speed horizontal shaft II4. As shown in Figs. 4 and 5 the shaft I21 is provided at its forward end with a pinion I23 that drives a pick-off gear I35 rotatably mounted on a stud I3I and meshing with another pick-off gear I32 fastened upon the end of a shaft I33. The pickoif gears I and I32 are made accessible by opening a door I34 in the front of the gear compartment I I3 in order that they may be removed readily and interchanged or replaced by other 7 ratio for adjusting the feed rate of the table.

The shaft I33 is provided at its inner end with a pinion I35 that meshes with a feed rate gear I36 on an overrunning clutch mechanism I31 through which power is transmitted to a table driving gear I33meshing with a gear I39 on a short shaft I4Iljournaled in the upper part of the saddle, as shown in the horizontal sectional view,

Fig. 7. The shaft I40 is provided at its forward end with a bevel pinion I that meshes with two similar bevel clutch pinions I42 and I43 rotatably mounted on a sleeve I44 as shown in Fig. 6. The sleeve I44 is splined on a table driving screw I45 and is retained in the saddle against longitudinal movement by abutment members I46 and I41 respectively. Slidably splined on the sleeve I44 between the clutch pinions I42 and I43 is a clutch spool I43 having clutch teeth at its ends arranged to mesh selectively with complementary clutch teeth of the pinions I42 and I 43 in such manner that the sleeve I44 may be rotated thereby in either direction or it may be' disconnected entirely from the driving pinions upon moving the clutch spool to its central neutral position.

The table driving screw I45 is rotatably mounted at its ends in boxes depending from the ends of the table 21 and it has threaded engagement with a nut mechanism I5-I stationarily mounted in the saddle, whereby rotation of the feeding screw I45 within the nut I 5I causes the screw and the table 21 to move longitudinally relative to the saddle 26. The screw I45 is provided with a squared end I52 at the left end of the table to which a crank may be applied for moving the table manually.

In order to avoid the occurrence of lost motion between the feed screw I45 and the stationary nut I5I, climb cutting without chatter or jerking, the nut I5! is arranged to be adjusted totightly engage the screw I45. As shown in Fig. 6, the nut I5I comprises complementary half nuts I54 and I55 GUI that are divider longitudinally along a horizontal axial plane, the lower half nut I54 being solidly mounted on the top of the saddle structure and having-end lugs I55 and I51, respectively disposed to engage the saddle in manner to prevent endwise movement thereof relative to the saddle. The upper half nut I55 is slidably mounted for limited longitudinal movement relative to the lower half nut I54 and is engaged at its left end by a threaded adjusting collar I58 that maybe turned to adjust the longitudinal position of the upper half nut relative to the lower half nut. When the upper half nut is forced to the right, as seen in Fig. 6, the threads thereof may be caused to tightly engage one side of the threads of the screw I45 and to force the other side of thethreads of the screw against the threads of the lower half nut I54, whereby the screw I45 is rigidly held in the stationary nut I5I and longitudinal lost motion is avoided.

to enable the machine to be used for A locking screw I53 is provided for locking the adjusting collar I56 in adjusted position.

The table 21 is provided at its rear edge with a centrally located coolant drain opening I62, shown in Fig. 5, the drain discharging into a coolant collecting trough I66 in the saddle 26 which communicates at its ends with catch pans or pockets I63 and I64 disposed respectively at the sides of the saddle 26 as shown in Fig. 6. The pans are arranged to catch coolant which may drip from the table, an extensible coolant discharge pipe I65 being provided to convey coolant from each pan individually to a coolant reservoir in the base of the machine, as shown in Fig. 1.

Power for moving the table 21 at rapid traverse rate is transmitted from the horizontal constant speed shaft II2 to a gear I61 rotatably mounted within the saddle and having splined connection with the end of the shaft II2 to permit relative longitudinal movement therebetween. The-,gear I51 meshes with a rapid traverse driving gear I66 that is mounted on a rapid traverse clutch mechanism I69 which is operative to selectively effect driving connection between the gear I68 and the table driving gear I38, the overrunning clutch mechanism I31 permitting the gear I38 to turn faster than the feed rate driving gear I35, whereby the gear I33 will drive the gear I39 and the bevel pinion MI in manner to move the table at rapid traverse rate.

For controlling the direction of movement of the table, means are provided to move the clutch spool I43 to engage it with either of the clutch pinions I42 or I43. As shown in Fig. 5, there is provided a shifting yoke or reversing fork I1 I which engages a groove in the clutch spool I48 and is slidably mounted for longitudinal movement in the saddle an opening I12 being provided therein for receiving a shaft. At its forward end, the reversing fork "I is provided with rack teeth I13 that are engaged by the teeth of a gear segment I14 formed on the inner end of a hollow control shaft I15that extends at the front of the saddle and is provided at its outer end with a feed control lever I16. When the' feed control lever I16.is in vertical central posiin its central or neutral position and out of engagement with both the clutch pinion I42 and the clutch pinion I43 and the table driving means is disconnected. To cause the table to be driven to the right, the feed lever I16 is moved to the right from its vertical position to engage the clutch spool I 48 with the clutch .pinion I 43, and to cause the table to move to the left, the lever is moved to the ieft to engage the clutch spool with the clutch pinion I42. I

In order that the clutch spool I43 may be moved by automatic control means to effect automatic stopping or reversing of the table, there is provided a slidabiy mounted reversing control rod III extending horizontally across the saddle parallel with the feed screw I45 and connected to the reversing fork III, as shown in Fig. 7. The control rod I'I'I is provided at its right end with three detent notches disposed to be enencircles and is slidably keyed to a vertically,

movable control plunger or tripping post I84. The rotatably mounted sleeve I88 is provided at its upper end with tripping abutments I85 that extend to the right and to the left thereof at the top of the saddle 26, as shown in Fig. 7 in such manner that when the clutch spool I48 is engaged with one of the clutchpinions to drive the table, the tripping abutments' I85 will be so turned from the neutral position shown in Fig. 7 that one of them will be positioned near the forward edge of the table 21 in the path of tripping means such as a stop dog I86 adjustably fixed on the front of the table. When the table is moved to the position in which the stop dog I86 engages the abutments I85, the control sleeve I88 will be turned to neutral position thereby disengaging the clutch I48 and stopping the table. After the table has been stopped by the stop dog I86, the feed lever I16 may be moved in direction to engage the clutch I48 with the other clutch pinion in order to move the table in the opposite direction. A similar but oppositely shaped stop dog may be provided at the other end of the table to stop it automatically in predetermined position when it is being moved in the other direction.

For effecting automatic reversal of the direction of table travel and for controlling the engagement of the rapid traverse clutch I68 to drive the table at rapid traverse rate there is provided a hydraulic control mechanism most of which is housed in the control compartment. I28 of the saddle 26. As shown in Fig. 'l the table reversing control rod I11 is provided at its left end with a piston I81 that operates in a cylinder I88 formed in the saddle and so arranged'that fluid pressure may be applied to either side of the piston to shift the rod. I11 either to the right or to the left as may be desired. The mechanism for hydraulically actuating the rapid traverse clutch I68 to operatively connect the rapid traverse driving shaft I22 with the table driving gear train, is shown in longitudinal section, somewhat diagrammatically, in the upper right hand corner of Fig. 18. As there shown,

the feed drivinggear I88 is operatively connected by means of an overload release clutch I8I with the overrunning clutch I81 that is'arranged to drive the shaft I82 to which the table drivin gear I88 is keyed, thereby'driving the table at the selected feed rate when the control mechanism is arranged for table drive at-feed rate. The rapid traverse clutch I68 is arranged to selectively connect the rapid traverse driving gear I88 to the shaft I82 to thereby enable the shaft I82 to be turned within the overrunning clutch I81 faster than the feed driving gear I88 whenever the clutch I68 is engaged.

For engaging the rapid 'traverse clutch I88. "there is provided a hydraulic cylinder and piston mechanism I88 that is arranged to exert force against the plates of the clutch-I68 to couple the gear I68 to the shaft I82 when pressure is admitted to the cylinder through a passageway I88 extending longitudinally through shaft I82 to one end thereof. When pressure is released from the passageway I84 a spring I86 moves the piston I88 in direction to release the plates of the clutch I68.

In order to prevent the table 21 from coasting or continuing to move at a rapid rate after the rapid traverse clutch I68 has been released, means are provided for rapidly retarding the shaft I82 to the speed of the feed rate driving gear I86. For this purpose there is provided .a

retarding clutch or brake I81 that is disposed to be engaged by the piston I88, moving under the influence of the spring I85, to frictionally couple the-feed rate driving gear I86 with the shaft I82, and thereby quickly reducing the speed of the shaft to that of the driving gear I86, whereupon driving action at feed rate will 'be promptly resumed through the overrunning clutch I88.

The hydraulic control mechanism for actuating the rapid traverse clutch I68 includes a rapid traverse control valve 28I, shown at the left in Figs. 4 and 13, from which a conduit 282 extends to a cap 288 at the end of the shaft I82, the cap 288 providing a rotatable connection with the passage I84 in the shaft I82. The rapid traverse valve 28I comprises a plunger 288 arranged for vertical movement within a valve body or sleeve 285 provided with valve ports, the conduit 282 being connected to a port 288. When the valve plunger 284 is raised from the position shown. in the drawings a land thereof uncovers I a pressure port 281 in manner to eifectmommunication with the port 286, whereupon liquid under pressure from a conduit 288 may flow through the port 281, the port 288, conduit 282, cap 288 and the passageway I84 to engage the rapid traverse clutch. When the valve stem. 288 is moved down to the position shown in the drawings, it closes the port 281 thus cutting off'the pressure source and at the same time opens another port 288 beneath the port 286 in manner to connect conduit 282 through the port 288 and the port 288 to a drain opening 2I8, whereby liquid from the cylinder I88 of the rapid traverse clutch may be forced by the spring I85 out through the passage I84 and the conduit 282 to the drain opening 2I8, thereby permitting the rapid traverse clutch to be released and the retarding brake I81 to be engaged.

For moving the valve plunger 284 up or down to control the rapid traverse clutch, there is provided at the front of the saddle a rocking control shaft 2I2, shown in Fig. 7, extending parallel with the control rod I11 and having at its left end an arm 2I8 provided with a rounded end engaging a slot 2I4 in the upper end of the valve plunger 284 whereby the plunger may be moved vertically upon rocking the shaft 2I2. As shown in Fig. 11, the arm M8 is provided with two detents that may be engaged by a spring pressed plunger 2I5 toretain the valve plunger 284 in either its upper or its lower position. As shown in Figs. 5 and 7, the rocking shaft 2I2 is provided at its right end with a crank arm 2I6 having a rounded end engaging a slot 2I1 in a horizontally disposed control rod 2 I8 that is slidably mounted within the hollow control shaft I15. At its outer end the rod 2I8 is provided with an opening 2I8 that is engaged by the lower end of the table control lever I18, the lever being so mounted on the hollow shaft I15 as to permit tilting movement thereof toward and from the table in manner to move the control rod 2I8 in or out to thereby turn'therockingshaft 2I2 for the lever I16 is pulled away from the table, the

valve plunger 284 is moved upward and the rapid traverse clutch I68'is engaged.

For effecting automatic operation of the rapid traverse clutch valve in response to movement of the table 21, the rocking shaft 2I2 is provided at the middle of the saddle with an arm 22I having a rounded end engaginga slot 222 in the vertically movable tripping post I84, as shown in Fig. 10. The tripping post I84 is arranged to be.

moved upwardly by an adjustably mounted tripping dog 223 shown in Fig. 4 on the front of the table, in manner to move the valve plunger 284 upward to engage the rapid traverse clutch. For disengaging the rapid traverse clutch, a tripping dog' 224 is adjustably fixed on the table in position to engage the tripping post I84 in manher to move it downward, thereby moving the valve plunger 284 down to the feed position, as

- shown in the drawings.

- shown in Fig. 2.

In order that the main spindle clutch 36 may I be operated either manually or automatically by meansof control apparatus carried by the saddle, hydraulic actuating mechanism'is provided for shifting the clutch control rod 38. As shown in Fig. 2, the clutch shifting collar 42 is engaged by a shifting fork 226 that is slidably mounted on a guide rod 221 and that is attached to an actuating or shifting rod 228 slidably mounted for horizontal movement'in a guide block 228. The shifting rod 228 is provided at its left end with a piston 238 that operates in a cylinder 23i mounted on the cover 58 of the gear box, as Pressure for ,actuating the piston 238 within the cylinder 23| is provided by a primary pump 232 shown in Fig. 2, and indicated diagrammatically in Fig. l3. Thepump 222 is arranged in the usual manner to pump the lubricating oil for lubricating the mecha' nism within the column 21 of the machine and it is connected by means of a conduit 233 to a pilot valve 234 associated with the cylinder 23! and arranged to control the operation of the hydraulic actuating mechanism for the main clutch 22.

For controlling the actuation of the spindle clutch 36 by means of the pilot valve 234 there is provided in the. saddle of the machine a spindle controlling valve 236 (Fig. 11) that is arranged to be actuated manually by means of a spindle controlling lever 231 and that is operatively connected to the pilot valve 234 by means of a control system including a single closed fluid passageway or hydraulic lead constituted by a flexible conduit 238 extending from the saddle v215 to the column 2|, as shown in Fig. 1.

As shown in Fig. 11, the spindle controlling valve 236 includes a valve body 248 mounted on the end of an operating shaft 24l that is connected by gearing 242 to a shaft 243 that carries the operating lever 231, whereby movement of the lever 231 from side to side causes the valve body 248 to turn within a valve casing 244, a detent mechanism 245 being provided for retaining the lever 23'! in either one of its two operating positions.

The valve body 248 is shown diagrammatically in developed form in Fig. 13 in position to permit control of the spindle automatically, the valve ports being shown in starting or running position and indicated by the broken dotted portions in stop position at the right of the running position.

Operating liquid under pressure for actuating the hydraulic control mechanism in the saddle 26 is derived from a secondary pump 241 shown in Fig. and that is arranged to pump liquid from the reservoir 12! in the bottom of the saddle, as shown diagrammatically in Fig. 13. From the pump 241 the liquid flows through a conduit 248 to a port 249 in the valve sleeve 244 which communicates with a groove 258 in the valve body 248 that in turn communicates with a port 25l to which is connected a conduit 252. The conduit 252 connects to a port 253 in a table reverse valve 254 disposed at the right of the rapid traverse valve 2M and shown in neutral position with the port 253 communicating with a port 255 from which the pressure conduit 288 leads to the port 281 of the rapid traverse control valve 2!. From the port 281 of the valve 28l a conduit 256 leads to a low pressure relief valve 251 that is ordinarily adjusted to open at a pressure of approximately 70 pounds to the square inch in the conduit 256. From the low pressure conduit 256 a conduit 258 leads to a circumferential groove 258 in the valve body 248 that has a branch groove 268 which communicates with a port 26| when the valve is in the running position shown in Fig. 13. From the port 261 a conduit 262 leads to a port 263 of the rapid traverse valve 281 which is shown in communication with a port 264 that connects with the flexible conduit 238 extending from the movable saddle to the pilot valve 234 on the column of the machine.

With the spindle control valve 236 in the position shown in Fig. 13, the operating liquid from the pump 241 exerts pressure through the valve connections just described and through the single flexible conduit 238 to the pilot valve 234 in manner to exert force upon the right end of a valve plunger 261 forcing it to the left against the resistance of a spring 268 which functions continuously to'urge the plunger to the right as shown in Fig. 13. When the pilot valve plunger 261 is in the left position, liquid from the primary pump 232 in the column enters the pilot valve from the conduit 233 through a port 269 that then communicates with a port 218 from which the liquid passes through a conduit 211 to the left end of the clutch operating power cylinder 23!, moving the piston 238 to the right as shown in Figs. 2 and 13, to engage the main clutch 36 for end of the piston draining through the valve 234. When the piston 238 has been moved to its extreme right position, a port 212 in the wall of the cylinder is uncovered to permit the operating liqbid to enter a conduit 213 from which it passes through a port 214 of the pilot valve to a conduit 215 that is connected to the lubricating system for lubricating the mechanism in the column of the machine.

When the spindle control lever 231 is moved'to its stop position to stop the spindle, the spindle control valve body 248 is moved in manner to position the ports as shown in dotted lines in Fig. 13, whereupon the port 26l is disconnected from the actuating pressure exerted through the groove 253 and the. groove 268, and is connected with a groove 211 which is provided with a drain opening 212. This results in relieving the fluid pressure from the pilot valve 234, whereupon the plunger 261 thereof moves to the right under the influence. of the spring 268 and forces the operating liquid back through the flexible conduit 238, through the valve ports 264 and 263 and the conduit 262, to the port 261 from which it then escapes through the groove 211 and the drain opening 218. With the spindle control valve thus in spindle stop position, the port 249 is brought into communication with a branch. of the low pressure groove 258 in order that low pressure the ports 263 and 218 is closed thereby cutting off the supply of operating pressure from the pump 232 to the left end of the clutch operating cylinder 23 I. At the same time a passageway is opened to place the port 269 in communication with a port 219 from which the liquid passes through a conduit 288 to the right end of the clutch actuating cylinder 23!, whereupon the piston 238 is moved to the left to disengage the spindle clutch 36. When the piston 238 moves to its left position, the port 212 is again uncovered and the liquid from the pump 232 flows through the conduit 213 and the port 214 to the lubricating supply conduit 215. The liquid in the left end of the cylinder 23! is forced out through the conduit 21! into the port 218 that has been placed in communication with a port 28! from which the liquid escapes through a drain 282.

In order to effect automatic reversal of the direction of movement of the table 21, there is provided a trip mechanism including two trip plungers 285 and 286 shown in Fig. 4, that extend upwardly from the top of the saddle 26 into the I path of a reversing dog 281 adjustably positioned on the front of the tablefthe plungers 285 and 286 being" operatively connected to actuate the reversing valve 254. As shown in Figs. 4 and 13, the reversing valve 254 comprises a plunger 238 that is slidably mountedwithin a valve sleeve 289 in'manner to be moved either up or down from its neutral or central position, a spring 298 being provided for resiliently holding the plunger trip plunger 286, the yoke 295 being shaped at' 'its mid-portion to encircle the control sleeve I83 in spaced relation thereto and being pivoted midway between its ends in the saddle. When the valve plunger 288 is in its central or neutral position as shown in Fig. 4 the trip plungers 285 and 286 extend equally. above the top of the saddle. v

When the table 21 in travelling from right to left as shown in Fig. 4, moves to a position in which the reversing dog 281 engages the trip plunger 286 in manner. to force it downward,

the rocker arm 295 moves the other trip plunger 285 upward and the rocker arm 292 moves the valve plunger 288 downward within the valve sleeve'289. When the valve plunger 288 is moved downward, a land 298 thereof closes a passageway between the port 253 and the port 255 thereby stopping off the flow of fluid from the pump 241 to the low pressure relief valve 251, whereupon the pressure delivered by the pump through the conduit 248 the valve 248 and the conduit 252 will build up to a pressure sufficiently high to be released through a high pressure relief valve 299 that is ordinarily set at a pressure of approximately 300 pounds to the square inch. The surplus liquid escaping through the relief valve 299 passes into the conduit 256 from which it may flow through the low pressure relief valve 251, thereby maintaining liquidat low pressure in the conduit 256 for actuating the rapid traverse clutch and in the conduit 258,

the groove 259, port 26! and theconduit 262 for acting upon the pilot valve plunger 267! to maintainthe main clutch 36 in engaged position.

' 7 When the valve plunger 288 moves downwardly a sufflcient distance to register a groove 38! thereof with a valve port 382, to which the conduit 252 is connected, liquid at high pressure will flow from the conduit 252 through an opening 383 extending longitudinally through the plunger 288 from the groove '38I to a cylinder 384 formed at the upper end of the valve sleeve 289 in manner to exert pressure on the upper end of a piston portion 385 of the valve plunger to quickly force the plunger downward to its lowest position.

When the plunger 288 arrives at its lowest position the port 382, connected with the high pressure supply conduit 252, is also placed in communication with a port 386 connecting with a conduit 88? that conveys the high pressure liquid to the left end of the reversing cylinder I88 whereupon the reversing piston I81 is moved to the right to move the reversing clutch I48 into engagement with the table driving bevel pinion I43, thereby reversing the direction of travel of the table to cause it to move from left to right. Liquid in the right end of the cylinder I88 is forced out through a conduit 388 that connects with a port 389 in the valve sleeve 288 from which the liquid flows through the valve to a port 3!!! and escapes through a drain 3! i.

In order that the movement of the table in reverse direction may be caused. to take place at rapid traverse rate, the reversing cylinder I88 is provided with a centrally disposed port 3!.3 which is uncovered when the pistonv I81 arrives at the right end of the cylinder whereupon the liquid under high pressure flowing through the conduit 381 and the cylinder I88 passes through a conduit 3I4 to aport 3I5 in the upper end of the valve sleeve 288 and thence by a conduit 3I6, also connected directly to the port 3I5 to a port 3I1 in the sleeve 286 in the rapid traverse valve 28!. As shown, the port 3" communicates with a cylinder 3I8 in the upper part of the rapid traverse valve in manner to apply the high pressure below a piston 3!!! formed on the vaive stem 284, whereupon the stem 284 is quick moved upward to rapid traverse position, there by connecting the low pressure supply condui 256 to the rapid traverse clutch actuating conduit 282, as previously explained.

When the rapid traverse plunger 284 arrives at its upper or rapid traverse position, the piston 3I9 thereof uncovers a port 828 that communicates through a conduit directly with a port .322 in the cylinder 384 at the top of the reversing valve 258. At the same time a port 323 in the valve plunger 288 is brought into communication with the cylinder 3I8v to permit the liquid to flow through a longitudinal passageway 324. to the lower end of the valve 28d. From the longitudinal passageway 324 the liquid escapes through another port 328 in the'plunger and enters a port 828 that is directly connected by a conduit 326 with a port 321 in the lower end of the reversing valve sleeve 288, in manner to exert pressure upwardly on a piston 328 formed on the plunger 288. The upward force exerted on the piston 328 quickly counter-balances the downward force exerted on the piston 385 in such' manner that the reversing plunger 288 is permitted to move promptly to its neutral position under the influence of the spring'298, the pressure on the pistons 328 and 385 being subsequently relieved through bleeder holes in the conduits 32! and 328. fiivhen the plunger 288 moves to neutral position, the pressure to the reversing cylinder I88 is cut oil by reason of the fact that the port ner, the piston I81 is freed from hydraulic resistance to permit the reversing mechanism to be actuated mechanically without interference.

The rapid traverse plunger 204 remains in its upper position by reason of the retaining detent mechanism 2I5 shown in Fig. 11 and as pressure .upon it has been relieved, it likewise may be moved by the mechanical actuating mechanism without resistance from the hydraulic system. With the valve piston 288 in its neutral position and the port 302 from the conduit 252 closed, the port 253 is again placed in communication with the port-255 whereupon the high pressure liquid in the conduit 252 escapes through the ports 253 and 255 into the conduit 208 and thence through the port 201 to the low pressurev conduit 256 from which it escaped through the low pressure relief valve 251, thereby. relieving the pump 241 from the necessity of providing further liquid at high pressure.

To prevent marring of a workpiece by a cutting tool in the spindle 22 when the table 21 is reversed at rapid traverse rate, it is desirable that the spindle be brought to a stop simultaneously with automatic reversal of the direction of table movement. For this purpose the lower part of the rapid traverse valve plunger 204 is provided with a land 33I that closes the port 263 when the valve is moved to rapid traverse position thereby cutting oil the supply of low pressure liquid from the conduit 262 to the flexible conduit 238. At the same time a land 332 of the valve piston 204 opens a port 333 in manner to permit the liquid in the spindle clutch pilot valve 234 to flow back through the flexible conduit 238, the ports 264 and 333 into a conduit 334 that connects with a port 335 of the spindle control valve 236 which in turn cormnunicates with the groove 211 of the valve body 240 in manner to permit the liquid to discharge through the drain 218. The spring 268 of the pilot valve 234 is then free to move the valve piston 261 to the right in manner to connect the primary pump 232 to the right end of the clutch operating cylinder 23I, as previously explained, thereby disenplunger 204 down to the feed position, whereupon the table is quickly retarded to feed rate by action of the retarding brake I91 as previously described, and the table will then continue to the right at the selected feed rate. When the plunger 204 moves down to the feed position, the land 332 closes the port 33 and the land 33I opens the port 263," thereby reestablishing pressure in the flexible conduit 238 to the pilot valve 234 and reengaging the clutch 36 to start the spindle. To effect automatic reversal into movement at rapid traverse rate in the opposite direction, there is provided another reversing .dog similar to the dog 281 at the other end of the table which is positioned to engage the trip plunger 285, moving it downward and turning the rgcking arm .282

in direction to raise the reversing valve plunger 288. When the valve plunger 288 moves upward the low pressure port 253 is closed by a land 336 of the plunger, Fig. 13, and pressure in the conduit 252 builds up as previously described. Upon further upward movement of the plunger, high pressure from the port 302 enters a groove 331 connecting'with a passageway 338 through the plunger to the lower end thereof from which the liquid escapes into the chamber 321 and exerts pressure upon the piston 328 to quickly move the plunger 288 upward to reverse position, the liquid in the cylinder 304 at the topof the valve escaping-meanwhile through the bleeder-hole in the passageway 32I and through the passageway 303. The high pressure liquid then flows from the port 302 to the port 303 and thence through the conduit 308 to the right side of the reversing piston I 81 moving it to the left to engage the reversing clutch I48 with the clutch pinion I42 for driving the table from right to left. The liquid in the left end of the cylinder I88 is forced out through the conduit 301, and port 306 to a drain port above the port 306 that is uncovered by upward movement of the land 336.

When the piston I81'arrives at its left position it uncovers the port 3 I3 permitting the high pressure liquid to pass through the conduit 3, the port 3I5, the conduit 3I6, and the port 3I1, to lift the piston 3 I 9 of the rapid traverse valve stem 204 thereby effecting engagement of the rapid traverse clutch I68 to cause the reverse movement to take place at rapid traverse rate. The rapid results in relieving pressure from both ends'of the reversing cylinder I88.

In order that the reversing piston I81 may be relieved of the necessity for exerting excessive force in disengaging the reversing clutch I48 against the frictional resistance thereof when under load, it is desirable that a stop dogI86 be positioned in front of the reversing dog 281, as

shown at the right end of the table in Fig. 4,

whereby the stop dog will engage the abutment I85 of the control sleeve to positively move the clutch148 nearly to its disengaged position be-.

fore the reversing plunger 286 is depressed.

If it is desired to operate the machine without stopping the spindle when the table is automatically reversed at rapid traverse rate, the valvev body 240. of the spindle control valve 236 maybe turned independently of the spindle controlling lever-231 within the valve sleeve 244 to a second operating position that is indicated diagrammatically in liig. 12. Turning of the valve body 240 to its other operating position is accomplished by withdrawing a locking pin 340, shown in Figsffi and 11, that is carried on an arm.34I keyed tothe shaft 243. from a positioning hole 342 in the hub of the lever 231 and moving it to a second positioning hole 343, thereby turning the valve body 240 relative to the operating lever 231. In Fig. 12 the valve body 240 is shown in the second operating position with the ports of the sleeve 244 indicated in solid lnes in the spindle starting or running position and in dotted lines in the spindle stop position. In

. escape through either the port 2'63 or the port 333 of the rapid traverse valve, through the conduit 262 or the conduit334 and thence through the groove 2'" to the drain opening 218. When the valve body 240 is moved to the spindle running position, both the port 26I and the port 335 (shown in full lines) are connected with a groove 345 that connects with the low pressure 'groove 259, whereby liquid at low pressure is applied to both the conduit 262 and the conduit 334 and may pass through either the port 263 or the port 333 into the port 264 and thence through the flexible conduit 238 to engage the main clutch 36, regardless of whether the rapid traverse plunger 204 is in the upper or the lower position. Consequently the spindle will continue to operate when reversal takes place at rapid traverse rate and it will be under the control of the manually operable spindle control lever 23! exclusively.

When the spindle control lever 231 is moved manually toits stop position to stop rotation of thespindle, the control valve 236 functions to disconnect the source of fluid pressure from the reversing valve 254, thereby rendering inoperative the table reversing control mechanism and preventing unintentional operation of the work table through accidental actuation of the trip mechanism. As may be seen in Figs. 12 and 13, when the valve body 240 is turned to spindle stop position, the groove 250 is moved out of register with the pressure port 249 to cut off the supply of fluid pressure to the conduit 252. This prevents the flow of-liquid through the reversing valve 254 and the table reversing cylinder I88 to the rapid traverse valve actuating cylinder 3l8 and obviates the possibility of the rapid traverse valve being shifted by accidental depression of a reversing plunger which might otherwise cause unexpected movement of the table at rapid traverse rate.

From the foregoing explanation of the construction and operation of a preferred embodiment of the invention, it is apparent that the invention has provided an improved machine tool of simple and rugged construction that is versatile and convenient to operate and that embodies control features of advanced design.

Although only one embodiment of the invention has been shown and described, it will be apparent to those skilled in the art to which this invention relates that various modifications in the manner of constructing the machine may be effected without departing from the spirit and scope of the invention as defined in the subjoined claims.

What is claimed is:

1. In a milling machine the combination of a base, a column upstanding therefrom, a knee guided on said column for vertical reciprocation and including an outstanding horizontal slide- Way portion, a saddle having vertical side wall portions respectively adjacent opposite lateral edges of said slideway, a top portion connecting said side walls above said slideway and having slide surfaces engaging said slideway to guide said saddle for horizontal reciprocatory movement, and a bottom portion underneath said a table guided on said saddle top portion for horizontal reciprocation in a path transverse to the direction of saddle movement, a table transmission including an element carried by said saddle and shiftable for altering the transmission effect, a fluid operable shifter for said element, a fluid reservoir within said bottom saddle portion, and a pump receiving fluid from said reservoir and connected for operation of said shifter, said reservoir providing a wall portion having exteriorly spaced projections for radiation of heat from the fluid within the reservoir and forming an exterior wall portion of said saddle.

2. In a machine tool the combination of a tool support and a work support, a transmission for movement of one of said supports including a member shiftable to different positions respectively for diiferent transmission effects, a fluid operable shifter for said member, a first pressure fluid supply source alternatively connectible for shifter operation to effect theone or the other of said member positions, a first valve means shiftable for controlling the connection of said first source and shifter, means continuously urging said first valve means to a position effecting one connection of said first source and shifter, a second pressure fluid supply source connectible for shifting said valve means to a position effecting another connection of the first mentioned source and shifter, and a second shiftable valve means controlling the connection of said second source with said first valve means.

3. In a machine tool the combination of a rotatable tool support and a relatively bodily movable support, a transmission forone of said supports including a shiftable transmission member, a shifter for said member, a first pump alternatively connectible for operation of said shifter in opposite directions, a first shiftable valve means controlling the connection of said first pump, spring means continuously urging said first valve means in a direction to effect the one connection of said first pump, a second pump connectible for shifting said first valve means in the other direction and a second valve means controlling the connection of said second pump.

4. In a machine tool the combination of a tool support and a work support, a plurality of transmissions respectively for the different supports and each including a shiftable transmission member, a plurality of fluid operable shifters respectively for the different members, a plurality of pressure fluid supply sources respectively connectible with the different shifters, a plurality of valve means respectively controlling the shifter connection of the different sources, means continuously urging one of said valve means in one direction to effect one connection of the associated supply source and shifter, and means for shifting the last mentioned valve means in the other direction including a channel connection between said last mentioned valve means and the other supply source, and a third valve means shiftable for alternatively rendering said channel connection effective or inefiective.

5. In a machine tool the combination of a tool support and a work support, a plurality of transmissions respectively for the different supports and each including a shiftable member, a plurality of fluid operable shifters respectively for the different members, means for shifting one of said support member shifters alternatively in opposite directions including a first pressure fluid supply source connectible therewith and a first shlitable valve means controlling the connection of said first source, means for shifting the other of said support member shifters alternatiyely'in opposite directions including a second pressure fluid supply source and a second shiftable valve means controlling the connection of said second source, means continuously urging said first valve means in one direction, and means for shifting said first valve means in the other direction including a channel connection from said second supply source and shiftable valve means controlling said channel connection.

6. In a milling machine, a. column, a tool supporting spindle rotatably mounted in said column, powerdriving means in said column, a hydraulically operated ,clutch disposed to selectively connect said driving means to said spindle for rotating it, a primary pump mounted in said column for providing fluid pressure to actuate 0 said clutch, a hydraulically actuated pilot valve mounted in said column and arranged to control the operation of said clutch by said fluid'pressure from said primary pump, a knee projecting from and slidably mounted on said column, a hollow saddle structure shaped to conform with and to entirely encircle said projecting knee and slidably mounted thereon the lower part of said hollow structure serving as a reservoir of large capacity for operating liquid, a work supporting 3"- table slidably mounted on said saddle, operating mechanism mounted within said hollow saddle structure and connected to actuate said table, means disposed to transmit power from said driving means in said column to said operating mechanism in said saddle. hydraulic control mechanism mounted within said hollow saddl structure and operatively connected to control said operating mechanism therein, a secondary pump carried by said saddle and operative to 9 pump liquid from said reservoir for actuating said hydraulic control mechanism and for actuating said pilot valve in said column, a control valve mounted in said saddle and disposed to control the flow. of liquid from said secondary pump to said pilot valve and a single flexible conduit operatively connecting said control valve in said saddle to said pilot valve in said-column for controlling said hydraulically operated clutch from said saddle.

7. In a hydraulic control system for a mechanism, the combination with a primary source of fluid pressure for actuating saidmechanism, of a pilot valve connected to control the flow of fluid from said primary source to thereby control the operation of said mechanism' said pilot valve being resiliently urged to one position of operation and movable to another position of operation by.

fluid pressure, a secondary source of fluid pressure, a single closed fluid passageway operatively 0o connecting said secondary source of fluid pressure to said pilot valve for actuating it, and acontrol valve disposed to control the flow of pressure fluid through said passageway, whereby said pilot valve may be selectively moved to either operating position in response to the pressure impressed thereon by said secondary source throughsaid' passageway to thereby efl'ect control of said N mechanism. n 8. In a machine having relatively movable parts and having mechanism associated with one of said parts, a hydraulic control system for said mechanism including a primary source of fluid pressure for operating said mechanism, a pilot valve connected to control the flow of fluid from said primary source to said mechanism to thereby pilot valve, and means disposed to control the flow of fluid from said secondary source into said conduit whereby said pilot valve may be selectively moved to either operating position in accordance with the pressure impressed thereon by said 15 secondary source to thereby efl'ect control of said mechanism 9. In a hydraulic control system for a machine tool having a frame and a member carried by said frame in manner to be movable relative thereto, m the combination with a power driven element mounted in said frame, of a hydraulically operated clutch disposed to operatively connect saidpower driven element to actuate said machine, a pump mounted on said frame and connected to Q6 actuate said hydraulically operated clutch, a hydraulically operated valve on said frame connected to control the actuation of said clutch by said pump, a second pump mounted on said relatively movable member for actuating said hy- 30 draulically operated valve, control mechanism carried by said movable member and associated with said pump in manner to control the actuation of said valve by said pump, and a hydraulic lead connecting said control mechanism on said '35 movable member to said valve on said frame, whereby said hydraulically operated clutch in said frame may be controlled by mechanism carried by said relatively movable member.

10. In a hydraulic controlsystem for a milling '4 I machine having a column and a work supporting member carried by said column and movable relative thereto, the combination with a tool supporting spindle rotatably mounted in said column and power driving means therefor, of a hydrau- ,5 lically actuated clutch disposed to selectively connect said driving means to said spindle for rotating it, a pump'mounted in said column for proriding fluid pressure-to actuate said clutch,'a hydraulically actuated control valve mounted on said column and connected in manner to control the actuation of said clutch by fluid pressure from said pump, a second pump mounted in said relatively movable work supporting member for providing fluid pressure to actuate said control valve on said column, control mechanism carried by said work support and associated with said second pump in manner to control the fluid pressure exerted thereby for operating said valve, and means connecting said control mechanism on said no work support to. said control valve on said column for conducting fluid pressure to said valve, whereby operation of said spindle on said column may be controlled by said control mechanism on a said relatively movable work supporting member, 35

11. In a milling machine the combination of a rotatable tool spindle, a reciprocable table, a spindle transmission including an interruptor shiftable to alternative transmission connecting and interrupting positions, a table transmission 70 including a member shiitable to alternative positions respectively for different transmission effeet, a plurality of fluid operable shifters respectively for said interruptor and for said member,

a first pressure fluid supply source for said in- 15 terruptor shifter, a first valve means having different positions respectively connecting said first source and interruptor shifter for effecting the different interruptor positions, a second pressure fiuid supply source for said member shifter, a second valve means having different positions respectively connecting said second source and in one direction, and means continuously urging said first valve means in the other direction.

12. In a milling machine having a rotatable spindle and a work support reciprocable in a path transverse to the spindle axis, the combination of a spindle transmission including an interruptor shiftable for alternatively establishing or interrupting spindle rotation, a support transmission including shiftable reverser and rate change means, a plurality of independently operable controllers for said support transmission and respectively for operation of said reverser and of said rate change means, another controller operable for substantially simultaneous operation of said reverser and rate change means, a first fluid operable shifter means for said interruptor, a second fluid operable shifter means for said other controller, first and second fluid supply sources respectively for said interruptor shifter means and for said other controller shifter means, first and second shiftable valve means respectively controlling the connection of said first source and first shifter and of said second source and second shifter, and valve controlled ch'annel means for operation of said first valve means from said second source.

13. In a milling machine having a rotatable spindle and a work support reciprocable in a path transverse to the spindle axis, the combination of a spindle transmission including an interruptor shiftable for alternatively establishing or interrupting spindle rotation, a support transmission including means shiftable for reversing the direction of support movement, a plurality of fiuid operable shifter devices respectively connected for movement of said interruptor and of said shiftable reversing means, first and second fluid pressure supply sources respectively connectible with said interruptor shifter device and with said reverser shifter device, first and second shiftable valve means respectively controlling the connection of said first source and interruptor shifter device and of said second source and reverser shifter device, means continuously urging said first valve means in one direction, and valve controlled channel means for connecting said second source to shift said first valve means in the other direction.

14. In a milling machine, a column, a knee projecting from said column, a hollow saddle structure shaped to conform with and to entirely encircle said projecting knee and slidably mounted thereon for horizontal movement the lower part of said hollow structure serving as a reservoir of large capacity for operating liquid, 9. work supporting table slidably mounted on said saddle for horizontal movement, operating mechanism including feed rate selecting means mounted within said hollow saddle structure and connected to actuate said table, hydraulic control mechanism mounted within said hollow saddle structure and operatively connected to control said operating mechanism, and a pump carried by said saddle and operative to pump liquid from said reservoir to actuate said hydraulic control mechanism.

15. In a machine tool, the combination with a movable element and power driven means for moving said element selectively at a selected feed rate or at rapid traverse rate, of clutch mechanism for selectively connecting said power driven means to operate said movable element, comprising an overrunning clutch device disposed to connect said power means for driving said element at feed rate and arranged to permit operation of said element at rapid traverse rate without interference from said feed rate drive, a friction clutch disposed to selectively connect said power means for driving said element at rapid traverse rate independently of said feed rate drive, and a second friction clutch arranged to frictionally connect said feed rate power means with said element when said first clutch is disengaged to synchronize said element therewith, whereby the rate of travel of said element may be quickly changed from rapid traverse rate to feed rate. 16, In a machine tool having a frame and a movable element carried by said frame, the combination with power driven means for moving said element at a selected feed rate and other power driven means for moving said element at to selectively connect said rapid traverse rate driving means to said movable element to drive it at rapid traverse rate said overrunning clutch functioning to permit rapid traverse movement thereof, and a retarding friction clutch operative to frictionally connect said movable element to said feed rate driving means when said rapid traverse clutch is disengaged to thereby retard said movable element to the speed of said feed rate driving means for effecting driving thereof through said overrunning clutch, whereby the rate of movement of said movable element may be quickly reduced from rapid traverse rate to feed rate to prevent overrunning thereof.

1'7. In a machine tool having a frame and a movable element carried by said frame, the combination with power driven means for moving said element at a selected feed rate and other power driven means for moving said element at rapid traverse rate, of clutch mechanism for selectively connecting said power driven means in manner to operate said movable element at feed rate or at rapid traverse rate, comprising an overrunning clutch device disposed to connect said feed rate driving means to said movable element to drive it at feed rate and arranged to permit operation of said element at rapid traverse rate without interference from said feed rate driving means, a rapid traverse friction clutch arranged to selectively connect said rapid traverse rate driving means to said movable element to drive it at rapid traverse rate said overrunning clutch functioning to permit rapid traverse movement thereof, a synchronizing friction clutch operative to frictionally connect said movable element to said feed rate driving means, and a hydraulically actuated operating memberarranged to effect 

